After eight months fighting in Syria they were arrested on their return to Heathrow Airport in January after their relatives tipped off counter-terrorism detectives.

Sarwar had left a note for his mother that he was going 'to do jihad' in Syria was 'doing the best deed in Allah's eyes'. He said the Taliban and Al Qaeda 'are not bad', so she went to the police.

After returning to Britain they told officers they had been doing humanitarian work but a camera containing 'thousands' of images, including some of them posing with guns on the front line, was found in their luggage.